ZetaTalk: Trajectories
Note: written on Feb 15, 1996.

Trajectories that parallel the surface of a large object exerting a strong gravitational pull lob up, then curve, and finally drop straight down, upon close examination.
Some shots low to the ground barely get into their downward drop before arriving on the surface, and thus this point is missed on those not astute. But videotaped
trajectories, examined in a frame by frame manner, display this scenario:

The object desires to go in a straightline, in the direction pointed in and impelled.

As the gravity pull is at its side, the straight line is diminished into a curve, as the drop of the object due to gravity is superimposed on the trajectory. The
magical curve, in fact, is a combination of linear momentum and gravity drop.

When the object reaches its apex, the linear momentum no longer is away from the gravitational giant, as the object now is pointed toward the giant. This is a
significant turning point, no pun intended, as from this point forward the object now finds that its linear momentum and its gravity drop are combined, and
thus, with this combined force, it ends up heading straight down.